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    <title>mtlb_isfield</title>
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    <center>M2SCI function</center>
    <div align="right">Last update : 29/07/2004</div>
    <p>
      <b>mtlb_isfield</b> - Matlab isfield emulation function</p>
    <h3>
      <font color="blue">Description</font>
    </h3>
    <p>There is no Scilab equivalent function for Matlab <tt>
        <b>isfield(st,f)</b>
      </tt> and equivalent expressions behave differently in some particular cases:</p>
    <dl>
      <dd>
        <b></b>
        <dd>
          <li>
            <b>
              <font color="maroon"></font>
            </b>
        If <tt>
              <b>st</b>
            </tt> is not a structure: Scilab equivalent returns an error message but Matlab returns <tt>
              <b>0</b>
            </tt>.
        </li>
        </dd>
      </dd>
    </dl>
    <p>
    The function <tt>
        <b>mtlb_isfield(st,f)</b>
      </tt> is used by
    <tt>
        <b>mfile2sci</b>
      </tt> to replace <tt>
        <b>isfield(st,f)</b>
      </tt> when it was not
    possible to know what were the inputs while porting Matlab code to Scilab. This function will
    determine the correct semantic at run time. If you want to have a
    more efficient code it is possible to replace <tt>
        <b>mtlb_isfield</b>
      </tt> calls:
    </p>
    <dl>
      <dd>
        <b></b>
        <dd>
          <li>
            <b>
              <font color="maroon"></font>
            </b>
        If <tt>
              <b>st</b>
            </tt> is a structure
        <tt>
              <b>tf = mtlb_isfield(st,f)</b>
            </tt> may be replaced by <tt>
              <b>allf=getfield(1,st);tf=or(allf(3:$)==f);</b>
            </tt>
          </li>
          <li>
            <b>
              <font color="maroon"></font>
            </b>
        If <tt>
              <b>st</b>
            </tt> is not a structure
        <tt>
              <b>tf = mtlb_isfield(st,f)</b>
            </tt> may be replaced by <tt>
              <b>tf=%F;</b>
            </tt>
          </li>
        </dd>
      </dd>
    </dl>
    <p>Caution: <tt>
        <b>mtlb_isfield</b>
      </tt> has not to be used for hand coded functions.</p>
    <h3>
      <font color="blue">See Also</font>
    </h3>
    <p>
      <a href="../programming/getfield.htm">
        <tt>
          <b>getfield</b>
        </tt>
      </a>,&nbsp;&nbsp;</p>
    <h3>
      <font color="blue">Authors</font>
    </h3>
    <dl>
      <dd>
        <b></b>V.C.</dd>
    </dl>
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